Exploring the Immune System's Role in Endometriosis: Insights Into Pathogenesis, Pain, and Treatment

: Endometriosis is a common gynecological condition that usually affects women during their reproductive years. The main goal of this narrative review is to understand the role of the innate and adaptive immune system in the pathogenesis of endometriosis and to explore ways to diagnose and treat endometriosis effectively. Methodology: A comprehensive literature search was conducted across PubMed, EMBASE, Cochrane, and Scopus. Full-text articles in English published between January 2019 and January 2025 were included in this review. Two independent reviewers screened titles and abstracts using preset inclusion and exclusion criteria, as well as relevant keywords related to endometriosis, immune responses, and chronic pain. Of 6,728 initially identified studies, 53 met the inclusion criteria after applying exclusion parameters. Recent papers shed light on the role of the immune system in the pathogenesis of endometriosis. The dysregulation of immune system cells, such as macrophages, natural killer cells, neutrophils, dendritic cells, T cells, and B cells, contributes to the pathogenesis of endometriosis by enhancing the development and progression of endometriosis lesions, thereby creating an inflammatory environment. The presence of the inflammatory environment not only supports the survival and growth of the ectopic endometrial lesion but also plays a vital role in the pain associated with it. Endometriosis is a disease characterized by the presence of ectopic endometrial-like tissue outside the uterine cavity. It is believed that this ectopic endometrial tissue is a result of an interplay between hormonal, immune, and environmental factors. To this day, the gold standard for diagnosing endometriosis is through laparoscopic surgery, and there is no long-lasting effective medical treatment.